Real Madrid won Wednesday's shootout 4-2 after a 2-2 draw on aggregate to qualify for the quarter-finals, with Atletico coach Diego Simeone casting suspicion on the decision to rule out Alvarez's spot-kick.

The Argentina international was deemed by VAR to have kicked the ball twice, touching it with his standing foot as he slipped before striking to score.

"Although minimal, the player made contact with the ball using his standing foot before kicking it," UEFA said in a statement.

"Under the current rule, the VAR had to call the referee signalling that the goal should be disallowed."

However, European football's governing body said it would hold talks with the sport's lawmakers regarding the rule on double touches.

"UEFA will enter discussions with FIFA and IFAB to determine whether the rule should be reviewed in cases where a double touch is clearly unintentional," it added.

Simeone said he wanted to believe the officials got the penalty decision right.

"I've never seen a penalty where they've called the VAR, but well, they would have seen that he touched it, I want to believe, I want to believe they saw he touched it."

The coach asked members of the media during his press conference to raise their hand if they had seen a replay in which it was clear Alvarez had touched the ball twice.

"Raise your hand, anyone who saw Julian touch it twice, who is going to raise their hand? Nobody has raised their hand," shouted Simeone.